摘要
为探明甲烷在钯基二聚体催化剂上脱氢反应过程的微观机理,对甲烷燃烧催化剂的设计与使用提供指导。在M06L/6-311++G(d,p)+SDD//M06L/6-311G(d,p)+LANL2DZ基组水平上,采用密度泛函理论(DFT)对甲烷在钯基二聚体催化剂(Pd2、PdPt和PdNi)上的脱氢过程进行了研究。对比了甲烷在催化剂Pd2、PdPt和PdNi上反应的能垒(Eb)、活化能(Ea)及反应速率常数(k),结果表明:CH2→CH是甲烷在二聚体Pd2反应的速率控制步骤(RDS),而CH3→CH2是催化剂PdPt和PdNi反应的RDS;钯基二聚体催化剂对甲烷脱氢的催化活性顺序为PdPt>Pd2>PdNi;抗积炭性能顺序为PdNi>Pd2>PdPt。PdPt适用于要求催化效率较高的项目,而抗积炭性能较好的PdNi催化剂可用于大型工业催化。
The study of the mechanism of methane dehydrogenation on Pd-based dimer catalyst can provide a guidance for the design and selection of catalyst on methane combustion.The processes of methane dehydrogenation on three Pd-based dimer catalysts(Pd 2,PdPt and PdNi)are investigated using the density functional theory(DFT)calculation under the M06L/6-311++G(d,p)+SDD//M06L/6-311G(d,p)+LANL2DZ level.The energy barrier(E b),activation energy(E a),and reaction rate constant(k)of methane dehydrogenation on Pd 2,PdPt and PdNi are compared.The results indicate that CH 2→CH is the rate-determining step(RDS)for methane dehydrogenation on dimer Pd 2,while CH 3→CH 2 is the RDS on PdPt and PdNi;the catalytic activity for methane dehydrogenation on Pd-based dimer catalyst follows the order of PdPt>Pd 2>PdNi;the anti-carbon performance follows the order of PdNi>Pd 2>PdPt.PdPt is suitable for those cases requiring higher catalytic efficiency,while PdNi catalyst is suitable for large-scale industrial production due to the good anti-carbon property.
作者
牟川淋
蒲韵霜
余洋
邓淇铮
唐子钰
王林元
邓洪波
Mou Chuanlin;Pu Yunshuang;Yu Yang;Deng Qizheng;Tang Ziyu;Wang Linyuan;Deng Hongbo(School of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu,Sichuan,China;Chengdu Natural Gas Chemical Plant General,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan,China)
出处
《石油与天然气化工》
CAS
CSCD
北大核心
2020年第3期39-47,共9页
Chemical engineering of oil & gas
关键词
甲烷脱氢
密度泛函理论
钯基催化剂
二聚体催化剂
methane dehydrogenation
density functional theory
Pd-based catalyst
dimer catalyst
